Leonardo da Vinci’s Canal Lock


Leonardo da Vinci’s Invention for the canal lock was one of his most enduring achievements. The lock he invented – the miter lock, is still in use today at almost any canal or waterway you visit in the world.

His original drawing is shown below –


Leonardo da Vinci’s Canal Lock

Leonardo’s invention for the miter lock


who invented canal locks

Leonardo da Vinci Canal lock – Milan, Italy


This is one of his inventions that was immediately taken into his local surroundings, and it slowly spread worldwide over the course of a couple of centuries. The locks it replaced were inefficient, cumbersome and very heavy. Usually it took either one man working very hard or two men sharing the load to lift one of the old locks against the force of gravity. Leonardo’s design was more efficient, easier to move and did its job exactly as intended when the locks were invented.

As the name implies, Leonardo’s miter lock was mitered, that is, two 45 degree angles meeting each other at a point. When the oncoming water hit them it forced the two miters into each other which resulted in an even tighter seal between them.

The gate is like a door on hinges, forming a V-shape pointing upstream when closed. One of the great things about these gates is that not only are they easier to open and close, but the pressure of the water also presses the two miter joints together, which also makes the gate self-sealing. The pressure also prevents them from opening until the water levels on either side of the gate equalize. The sketch also shows the already common flap valve built into the gate to equalize the water level.

Below video showing the difference between Leonardo’s miter lock and the portcullis lock which it replaced, it also shows some modern day examples of Leonardo’s lock.



The canal lock is just one more example of how revolutionary Leonardo was, and another example of an invention of his that has survived the test of time long after its inventor, therefore, almost making the man himself immortal.